underbody corrosion spray

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I wanted to treat my new truck, as i do use my truck to get to work on call when we have ice and snow. Not every year here do we have snow. But they do spray a lot of brine on the roads beforehand.

@Trav Recommended this kit. As there are no underbody corrosion shops here in the south. I got it today. I've never treated under body before, I get that the body cavity wax is to be sprayed in rockers, frame channels etc. I'll also use that before the running boards are on.

But the rest of the underbody? Do i spray the cab/body mounts and the frame behind the wheels? The frame behind the front wheels?

On a 2500 truck i don't think this is enough to cover everything, so what should I hit for sure? Or should i order more and spray everything underneath?

Thanks.
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Spray the frame totally inside and out, inside wheel wells inside where the rear panels rot above the wheels from inside, do the whole underneath of the truck. You may need another kit depending on how thick you apply it, start with the frame and rockers.
 
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Spray the frame totally inside and out, inside wheel wells inside where the rear panels rot above the wheels from inside, do the whole underneath of the truck. You may need another kit depending on how thick you apply it, start with the frame and rockers.
Thanks Trav! I thought now would be the time,new, before dirt gets everywhere, and rust sets in. Rather than wait to just before winter.
 
Slightly off topic - I hope you wear a respirator while doing this. I cannot imagine sitting under the truck and spraying this stuff while in close proximity.
I was thinking a paint respirator would be the thing to use. I also have a large drum fan I was thinking of running to keep air moving . Not close enough to affect the spray, but enough to have better air .

I don't have a fresh air hood like hobby air or a capr
 
Slightly off topic - I hope you wear a respirator while doing this. I cannot imagine sitting under the truck and spraying this stuff while in close proximity.
I was thinking a paint respirator would be the thing to use. I also have a large drum fan I was thinking of running to keep air moving . Not close enough to affect the spray, but enough to have better air .

I don't have a fresh air hood like hobby air or a capr

Yes, don't cheap out on it either. A dual filter respirator with charcoal filters and the gauze pre-filters which go over the charcoal cartridges work well. Make sure you fit test it so it fits and filters properly. 3M makes a good one. https://www.amazon.com/6211PA1-Cartridge-Paint-Spray-Respirator/dp/B00QZ5I4KW
 
Any links to the kit in the OP? I thought they had to be purchased individually so this would be even better.
 
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Rockers, cab corners and wheel arches on the bed are the most important. My 2021 Chevy has plastic plugs in all those places making it super easy to coat those areas.
 
So I thought the rust prevention products in a spray can were thinner than what you get by the QT or Gal. Mainly for touch-ups. Is that true?
Yes they have to be thinner in order to atomize from a spray can. Some people use spray bombs for complete rust prevention though. Quarts and gallons are typically spray applied with an airless sprayer, HVLP or rust proofing gun, and thinned accordingly. In all honesty products sprayed via airless, HLVP or from a rust proofing gun if used properly will do a much better longer lasting job than a spray bomb.
 
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and anything's better than nothing.

Look for cavities where sand and road grit collect. They probably are already full. Clean 'em out (pressure washer?) and let that be your first target.

Also go after things like fuel filter fittings, brake lines and fittings, inside crossmembers, on top of the charcoal canister and fuel tank. Anything hanging underneath by thin dingle dangle metal.
 
So I thought the rust prevention products in a spray can were thinner than what you get by the QT or Gal. Mainly for touch-ups. Is that true?
Yes they have to be thinner in order to atomize from a spray can. Some people use spray bombs for complete rust prevention though. Quarts and gallons are typically spray applied with an airless sprayer, HVLP or rust proofing gun, and thinned accordingly. In all honesty products sprayed via airless, HLVP or from a rust proofing gun if used properly will do a much better longer lasting job than a spray bomb.
Probably not as good as the stuff you would use in a rustproofing gun. Trucks are not known for rusting as much here in the south. But being new, i wanted to add some protection, especially in the frame channels. Since its new, why not hit the rocker panels and fender wells etc.

I can't see driving up north for hours to get it sprayed , and with the low mileage i'll put on it, i can't see spending for a rustproofing setup.
 
Probably not as good as the stuff you would use in a rustproofing gun. Trucks are not known for rusting as much here in the south. But being new, i wanted to add some protection, especially in the frame channels. Since its new, why not hit the rocker panels and fender wells etc.

I can't see driving up north for hours to get it sprayed , and with the low mileage i'll put on it, i can't see spending for a rustproofing setup.
It still beats doing nothing. If you apply a few coats and touch up as needed you should be fine. I have a compressor with a good rust proofing gun, along with airless and HVLP sprayers from my painting business. I use the rust proofing gun for frame rails, inner panels, doors, etc, and hard to access areas with the wands. Then I use the airless sprayer for the undercarriage. That lays down a beautiful coat, quickly.
 
It still beats doing nothing. If you apply a few coats and touch up as needed you should be fine. I have a compressor with a good rust proofing gun, along with airless and HVLP sprayers from my painting business. I use the rust proofing gun for frame rails, inner panels, doors, etc, and hard to access areas with the wands. Then I use the airless sprayer for the undercarriage. That lays down a beautiful coat, quickly.
Out of curiosity, what does a rustproofing good m cost?
I have a good air compressor.
 
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